Front-end integral air-conditioning unit

ABSTRACT

A sub-unit for a vehicle air conditioning system is shipped with a condenser, chiller and fluid lines. Snap together couplings are placed on free ends of the fluid lines whereby the sub-unit can be pre-charged, shipped, installed into the front end of a vehicle engine compartment and connected to an air conditioning compressor.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims the priority of provisional application No.60/488,900 filed Jul. 21, 2003 and having the attorney docket numberDP-310287.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The subject invention relates to an air conditioning sub-unit for avehicle.

2. Description of the Related Art

In traditional air conditioning systems, a compressor, a condenser and achiller are individually installed into an engine compartment of avehicle and interconnected with fluid lines. After these components areinterconnected with the fluid lines, the circuit is filled with arefrigerant. This process adds a large amount of time and cost to thevehicle because of the assembly time required to install the individualcomponents and interconnect them with fluid lines plus the equipmentrequired to charge the circuit with the refrigerant.

Various assemblies are well known for providing a self-contained airconditioning circuit that is pre-filled with a refrigerant. Theseassemblies allow for the elimination of the charge equipment and theprocesses for filling the air conditioning circuit with refrigerantduring the vehicle assembly process. Additionally, these assembliesreduce the number of individual components that have to be installedinto the engine compartment of a vehicle. This is accomplished byproviding an air conditioning circuit that is pre-assembled andpre-charged with the refrigerant.

One such unit provides a circuit with a compressor, an evaporator, anaccumulator or receiver, and a condenser which are pre-assembled onto acommon support platform. Additionally, these components areinterconnected to one another such that they form a complete refrigerantcircuit. The circuit is pre-filled with refrigerant and sealed. Finally,the circuit is installed into the vehicle as a single sub-unit via thecommon support platform.

One problem with such a system is that in order to pre-fill the circuit,it requires fluid connection to the compressor. Therefore, when thecompressor is added to the overall assembly, the assembly becomes largerand heavier than if it could be pre-filled without the compressor. As aresult, installation of the circuit into the vehicle, with thecompressor attached, may require substantial tools to aide in liftingand maneuvering the circuit into the vehicle. Additionally, somecompressors are connected to the condenser and chiller at a distancerequiring long fluid lines. This length could be a bar to shipping thecircuit as a single pre-filled assembly.

BRIEF SUMMARY OF THE INVENTION AND ADVANTAGES

The subject invention provides a sub-unit for a refrigerant circuitincluding a condenser and a chiller in fluid communication with thecondenser. A high pressure fluid line is coupled to the condenser andextends to a free end and a low pressure fluid line is coupled to thechiller and also extends to a free end. A refrigerant is contained inthe condenser, in the chiller and in the lines. Finally, a valve isdisposed on each of the free ends for retaining the refrigerant in thesub-unit.

The subject invention also provides a method of fabricating and shippinga sub-unit for a refrigerant circuit that includes a condenser, anevaporator coupled to the condenser, a high pressure fluid line coupledto the condenser and extending to a free end, and a low pressure fluidline coupled to the chiller and extending to a free end. The methodcomprises the steps of placing a valve on each of the ends to retain arefrigerant in the sub-unit and then charging the sub-unit with therefrigerant through one of the valves.

Accordingly, it would be advantageous to provide an air conditioningsub-assembly, independent of the compressor, which is pre-filled andself-sealing. This would facilitate ease during vehicle installationwhile eliminating the refrigerant charge equipment that is typicallyused during vehicle assembly. Further, it would be advantageous toprovide an air conditioning assembly that is integrated as a singlesub-unit, thereby reducing the overall packaging for the multiplecomponents to packaging for a single sub-unit assembly.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Other advantages of the present invention will be readily appreciated asthe same becomes better understood by reference to the followingdetailed description when considered in connection with the accompanyingdrawings wherein:

FIG. 1 is a perspective view of a sub-unit for an air conditioningcircuit and compressor installed in the front of a vehicle enginecompartment;

FIG. 2 is a front view of a sub-unit for an air conditioning circuit;

FIG. 3 is a front view of a sub-unit and a compressor for an airconditioning circuit;

FIG. 4 is a front view of a sub-unit for an air conditioning circuitattached to an electric compressor connector;

FIG. 5 is a front view of a sub-unit for an air conditioning circuitattached to an accessory drive compressor connector;

FIG. 6 is a valve unit for a sub-unit for an air conditioning circuit inthe normally closed position;

FIG. 7 is a valve unit for a sub-unit for an air conditioning circuit inan open position; and

FIG. 8 is a flow diagram of a method of fabricating and shipping asub-unit for an air conditioning circuit.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the Figures, wherein like numerals indicate like partsthroughout the several views, a vehicle is generally shown at 10 in FIG.1 and comprises a body 22 that defines an engine compartment 16 having afront 18 and a rear 20 disposed in spaced relationship to the front 18and a passenger compartment 22 that is disposed proximate the enginecompartment.

An air conditioning system is disposed in the vehicle 10 and has twocircuits, an air conditioning circuit and a secondary circuit. The airconditioning circuit, shown in FIG. 3, is disposed in the enginecompartment 16, preferably at the front 18. The air conditioning circuitcomprises a sub-unit 12 and a compressor 42. The sub-unit comprises acondenser 30 that is connected to, and in fluid communication with, achiller 32. Preferably, the condenser 30 is disposed above the chiller32. A high pressure fluid line 34 is coupled to the condenser 30, and alow pressure fluid line 36 is coupled to the chiller 32. Each of thelines 34, 36 extends to a free end 38. A refrigerant is contained in thechiller 32, in the condenser 30 and in the lines 34, 36.

An expansion device 40, for expanding the refrigerant received from thecondenser 30, interconnects the condenser 30 and the chiller 32. Areceiver 54 and/or an accumulator 56 are used in the air conditioningcircuit. The receiver 54 typically interconnects the chiller 32 and thecondenser 30 and serves to hold excess refrigerant, remove acid andmoisture from the refrigerant, and filter debris from the airconditioning circuit. The accumulator 56 typically interconnects thechiller 32 and the free end 38 and serves to store and preventrefrigerant from entering the compressor 42 in the liquid state. Thecompressor 42, for the air conditioning circuit is for compressing andmoving the low pressure refrigerant received from the chiller 32,through the low pressure fluid line 36, and pumping it into thecondenser 30, through the high pressure fluid line 34.

The secondary circuit is a non-pressurized loop which carries a fluid,preferably a coolant, into and out of the chiller 32, through asecondary path, that is not connected to the air conditioning circuit.The fluid from the secondary circuit is cooled, by virtue of heatexchange, as it passes through the chiller 32, via the secondarycircuit. This chilled fluid passes from the chiller 32 and to one ormore liquid heat exchangers that are located in the vehicle passengerspace 22 via coolant hoses 26. The benefit of having the primary and thesecondary loops are that they permit the sub-unit 12 to be disposedanywhere in the vehicle 10 as a single unit, but preferably at the front18 of the engine compartment 16. This location in the engine compartment16 is ideal because it permits airflow to the condenser 30.

By utilizing a method of fabricating, pre-charging and shipping an airconditioning sub-unit 12, the air conditioning sub-unit 12 can beassembled, charged and shipped inclusive of the refrigerant andindependent of the compressor 42. The method first includes step 100 ofplacing a valve unit 44 on each of the ends for retaining therefrigerant in the sub-unit 12. Each of the valve units 44 has anormally closed position, shown in FIG. 6, which is movable to an openposition, shown in FIG. 7, in response to connection to a connector 50.Typically, the connector 50 is in fluid communication with thecompressor 42 for coupling the compressor 42 with the sub-unit 12.Therefore, when the valve units 44 are in the normally closed position,they are self-sealing and do not require a cap or plug for retention ofthe refrigerant. The open position allows the refrigerant to flow intoand out of the lines 34, 36. The changes in valve position arefacilitated by the valve unit 44 and the connector 50 defining a snaptogether coupling 52 that moves the valve unit 44 from the normallyclosed position to the open position when the valve unit 44 and theconnector 50 are snapped together. Furthermore, the snap togetherconnection 52 allows the pre-filled sub-unit 12 to be connected to thecompressor 42 without leakage of the refrigerant during or afterestablishment of the connection.

Next, the method incorporates the step 110 of charging the sub-unit 12with the refrigerant through one of the valve units 44. This can beaccomplished by connecting a connector 50, which is coextensive with arefrigerant charge machine, to one of the valve units 44 to establish anopen position. Following completion of charging the sub-unit 12, theconnector 50 is removed and the closed position is automaticallyresumed. This filling operation is performed prior to connecting thevalve units 44 to the compressor 42. The method next includes the step120 of shipping the sub-unit 12 with the refrigerant retained therein.As such, the sub-unit 12 can be fabricated and shipped separate from thecompressor 42 with the refrigerant retained therein.

The method then comprises the step 130 of inserting the sub-unit 12 intothe engine compartment 16 of the vehicle 10. Allowing the sub-unit 12 tobe inserted into the engine compartment 16 as a single, pre-filledsub-unit 12 can have several benefits. The sub-unit 12 can be tested forleaks at the sub-unit 12 assembly location, prior to delivery to thevehicle 10 assembly location. Additionally, by allowing the sub-unit 12to be pre-filled with the refrigerant, the refrigerant chargingequipment, and the resultant processing, can be eliminated at thevehicle 10 assembly location.

The next step 140 is inserting the compressor 42, having the connectors50, into the engine compartment 16 of the vehicle 10. In one form, thecompressor 42 can be an electric compressor, as shown in FIG. 4, whichis capable of being mounted proximate the sub-unit 12. Alternatively,the compressor 42 can be an accessory drive compressor, as shown in FIG.7, which is mounted to the engine and powered via a pulley connection tothe engine. With the accessory drive option, the compressor 42 islocated at a distance further from the sub-unit 12 than when using theelectric compressor. Accordingly, integral high and low pressure liquidlines are required and the distance between the compressor 42 and thesub-unit 10 can dictate that the length of these integral lines issignificant. These integral lines additionally require evacuation.

Finally, the method comprises the step 150 of snapping a connector 50 toeach of the valve units 44 for establishing an open position between thelines and the connector 50. With the establishment of these connections,the valve, units 44 move into the open position and allow therefrigerant to flow between the sub-unit 12 and the compressor 42. Thevalve units 44 and the connectors 50 further define the snap togethercouplings 52 that move the valve units 44 from the normally closedposition to the open position when the valve units 44 and the connectors50 are snapped together. The benefit of a snap together coupling 52 isthat the connection is capable of being established in a singlepress-together action. This connection can be established without theaid of tooling and also prevents leakage of the refrigerant prior to,during and subsequent to the establishment of the snap togetherconnection. The result of the connection is that the sub-unit 12 is influid communication with the compressor 42.

Obviously, many modifications and variations of the present inventionare possible in light of the above teachings. In addition, the referencenumerals in the claims are merely for convenience and are not to be readin any way as limiting.

1-12. (canceled)
 13. A method of fabricating and shipping a sub-unit fora refrigerant circuit of the type including a condenser, an evaporatorcoupled to the condenser, a high pressure fluid line coupled to thecondenser and extending to a free end, and a low pressure fluid linecoupled to the chiller and extending to a free end, said methodcomprising the steps of: placing a valve unit on each of the ends forretaining a refrigerant in the sub-unit; and charging the sub-unit withthe refrigerant through one of the valve units.
 14. A method forfabricating and shipping a sub-unit as set forth in claim 13 furthercomprising the step of shipping the sub-unit with the refrigerantretained therein.
 15. A method for fabricating and shipping a sub-unitas set forth in claim 14 further comprising the step of inserting thesub-unit into an engine compartment of a vehicle.
 16. A method forfabricating and shipping a sub-unit as set forth in claim 15 furthercomprising the step of inserting a compressor having connectors into theengine compartment of a vehicle.
 17. A method for fabricating andshipping a sub-unit as set forth in claim 16 further comprising the stepof snapping a connector to each of the valve units for establishing anopen position between the lines and the connector.